The application is that original bill application number is the application for a patent for invention (international application no: PCT/JP2010/000222 of No.201080001344.4, the applying date: on January 18th, 2010, denomination of invention: bidirectional switch circuit and comprise the power conversion device of this bidirectional switch circuit) divide an application.
Summary of the invention
The present invention researches and develops in view of above all points, its object is: two switch elements connect into can the bidirectional switch circuit of two-way admittance in, seek to reduce components and parts number and simplify circuit and reduce on-state losses, and obtain can be by the simple driving of switch element being controlled to the formation of two-way admittance.
-for solve the technical scheme of existing issue-
For reaching described object, in bidirectional switch circuit 30 involved in the present invention, be in switch element SW1, SW2, to apply the switch element SW1 of revers voltage, even if be configured to backward current under the state of not inputting conducting state driving signal on gate terminal G1, also circulate.
Specifically, the invention of first aspect, is to comprise that to connect into the bidirectional switch circuit of two switch element SW1, SW2 that can two-way admittance be object.And, described two switch element SW1, SW2 connect mutually, in described two switch element SW1, SW2, be applied in the switch element SW1 of the revers voltage that the voltage of voltage ratio drain D side of source S 1 side is high, even if be configured under the state of not inputting conducting driving signal on gate terminal G1, electric current also can be from source S 1 side direction drain D side flow.
According to above formation, be applied in the switch element SW1 of the revers voltage that the voltage of voltage ratio drain D side of source S 1 side is high, under the state of not driven control, also be in order to make electric current from this source S 1 effluent to drain D side, no longer need the diode that refluxes, also a plurality of switch elements of demand motive no longer.Therefore, by described forming, reduce the number of components of bidirectional switch circuit 30, so not only simplified the formation of circuit, also can seek to obtain the reduction of on-state losses.Also have, according to described formation, because no longer need all switch elements in bidirectional switch circuit 30 to drive control, so control, become easy.
In described formation, comprise the gate driver circuit 33 of controlling the switch element SW1 that is applied in described revers voltage in order to drive, described gate driver circuit 33, is included in the resistive element 44 (invention of second aspect) in parallel with this switch element SW1 between the source S 1 of described switch element SW1 and gate terminal G1.
By the resistive element 44 in parallel with this switch element SW1 between the source S 1 of described switch element SW1 and gate terminal G1 like this, the voltage between source S 1 and drain D, is all applied between gate terminal G1 and drain D substantially.Therefore, according to described formation, just can effectively increase the voltage between described gate terminal G1 and drain D, make as much as possible it promptly rise to the threshold voltage vt that described switch element SW1 becomes conducting state, can also make this switch element SW1 become reverse conducting state (can from source terminal to drain electrode conducting state).
Also have, by described such resistive element 44 is set, just can prevent from applying the withstand voltage such large voltage surpassing between source S 1 and gate terminal G1, just can prevent from destroying between the source S 1 of switch element SW1 and gate terminal G1 for this reason.
Also have, the switch element SW1 ' that is preferably applied in described revers voltage has: only allow electric current between gate terminal G1 and drain D from this gate terminal G1 effluent to parasitic diode Dgd1 between the gate-to-drain of drain D side, described switch element SW1 ', is constructed so that threshold voltage vt that this switch element SW1 ' becomes conducting state is than the forward voltage Vf of parasitic diode Dgd1 between described gate-to-drain little (invention of the third aspect).
Thus, electric current can not flow in the parasitic diode Dgd1 between the gate-to-drain being formed between gate terminal G1 and drain D, switch element SW1 ' becomes conducting state by the voltage between gate terminal G1 and drain D, and electric current flows in this switch element SW1 '.At this, if the upper circulating current of the parasitic diode Dgd1 between the gate-to-drain in switch element SW1 ', in this parasitic diode Dgd1, accumulated delay when minority carrier causes disconnecting, and the situation phase specific loss of flowing through switch element SW1 ' with electric current increases, but as mentioned above, by electric current is not flowed in parasitic diode Dgd1 between gate-to-drain, and electric current is flowed in switch element SW1 ', the generation of the delay in the time of just can preventing from disconnecting or the increase of loss.
Also have, preferably be applied in the switch element SW1 ' of described revers voltage, have only allow electric current between gate terminal G1 and drain D from this gate terminal G1 effluent to parasitic diode Dgd1 between the gate-to-drain of drain D side with in order to drive to control the gate driver circuit 51 of described switch element SW1 '; Described gate driver circuit 51, comprise the grid voltage adjustment part 54 of adjusting voltage Vgd between gate-to-drain, make between this gate-to-drain between gate terminal G1 and drain D voltage Vgd than the forward voltage Vf of parasitic diode Dgd1 between described gate-to-drain little (invention of fourth aspect).
Thus, really can make between the gate-to-drain between gate terminal G1 and drain D voltage Vgd less than the forward voltage Vf of parasitic diode Dgd1 between the gate-to-drain being formed between gate terminal G1 and drain D, for this reason, also just can more positively prevent between this gate-to-drain current flowing on parasitic diode Dgd1.
Also have, preferably include in order to drive respectively two gate driver circuits 33,34 of controlling described two switch element SW1, SW2, described gate driver circuit 33,34, be configured to each switch element SW1, SW2 separately on gate terminal G1, G2, input identical driving signal (invention aspect the 5th).
By doing like this, no longer need to change and drive the content of signal and the input time of this driving signal for each switch element SW1, SW2, so controlling, the driving of switch element SW1, SW2 just becomes easy.
In addition, as described formation, if simultaneously to each switch element SW1, SW2 input drive signal, due to departing from and switch element SW1 constantly, the deviation of the characteristic of SW2 etc. makes each switch element SW1, SW2 becomes the moment of conducting state to be departed from, also likely make to apply the destruction of the switch element of revers voltage, but as described in the invention of first aspect, even if what use as switch element is that the driving signal of input gate terminal G1 is the also structure of reverse flow of cut-off signal electric current, therefore, even if voltage reversal is applied to switch element SW1, on SW2, also can prevent this switch element SW1, SW2 damages.
Also have, preferably comprise and be configured to the control circuit 30 (invention of the 6th aspect) that disconnects control signal to being applied in the switch element SW1 output of described revers voltage.Thus, be applied in the backward current that circulates on the switch element SW1 of revers voltage, and really can interdicting the forward current of this switch element SW1 by this switch element SW1.That is to say, according to described formation, just can obtain the more positively bidirectional switch circuit 30 of switched conductive direction.
Also have, preferably described two switch element SW1, SW2 are arranged on a device with two gate electrodes (invention of the 7th aspect).By doing like this, two switch element SW1, SW2 just can have drain terminal, and the chip area of device also reduces accordingly.Therefore, just can reduce the loss of bidirectional switch circuit 30.
Also have, in the bidirectional switch circuit described in the invention aspect the 7th, the distance of described two gate electrodes preferably, than mutual correspondence gate electrode and the distance between the electrode of source large (invention of eight aspect).By doing like this, the distance that just can guarantee to contribute between two withstand voltage gate electrodes of switch element SW1, SW2 can be larger.
The 9th invention to the 12 aspect, relates to power conversion device.Specifically, in the invention of eight aspect, power conversion device, is to comprise using the bidirectional switch circuit described in the invention of first to fourth aspect either side as the matrix of switch portion, handing over-hand over transducer 60 (invention of the 9th aspect).By this, form, even if hand over-hand in transducer 60 at matrix, also can obtain the such effect of invention of first to fourth aspect.Particularly, in the invention aspect the 9th, preferably form described matrix and hand over-hand over two switch element Sur1, Sur2 of the switch portion of transducer 60 to be arranged on a device with two gate electrodes (invention of the tenth aspect).By doing like this, matrix hand over-hand in transducer 60, also can access with the described the 7th aspect the same effect of invention.In invention aspect the tenth, preferably the distance of described two gate electrodes is than mutually corresponding gate electrode and the distance between the electrode of source large (the tenth invention) on the one hand.By doing like this, to the distance between two gate electrodes of withstand voltage contribution of switch element (SW1, SW2), can guarantee greatlyr.
Also have, in the invention of the tenth aspect, power conversion device 1,1 ', comprises (invention of the 12 aspect) using first to the bidirectional switch circuit described in the invention of eight aspect either side as switch portion.By such formation, even if in comprising the power conversion device 1 of the bidirectional switch circuit such as power factor improvement circuit, 1 ', also can obtain the such effect of invention of described the 7th aspect.
The present invention also provides a kind of bidirectional switch circuit, comprise connect into can two-way admittance two switch element (SW1, SW2), wherein: described two switch element (SW1, SW2) series connection mutually, described two switch element (SW1, SW2) in, be applied in the switch element (SW1) of the revers voltage that the voltage of voltage ratio drain electrode (D) side of source electrode (S1) side is high, even if be configured to and not yet input the state that conducting drives signal on gate terminal (G1), electric current also can be from source electrode (S1) side direction drain electrode (D) side flow, be applied in the switch element (SW1 ') of described revers voltage, in gate terminal (G1) and drain electrode, have between (D) and only allow parasitic diode (Dgd1) between the gate-to-drain of electric current from this gate terminal (G1) effluent to drain electrode (D) side, described switch element (SW1 ') be configured to, make this switch element (SW1 ') become the threshold voltage vt of conducting state less than the forward voltage Vf of parasitic diode (Dgd1) between described gate-to-drain.
The present invention also provides a kind of bidirectional switch circuit, comprise connect into can two-way admittance two switch element (SW1, SW2), wherein: described two switch element (SW1, SW2) series connection mutually, described two switch element (SW1, SW2) in, be applied in the switch element (SW1) of the revers voltage that the voltage of voltage ratio drain electrode (D) side of source electrode (S1) side is high, even if be configured to and not yet input the state that conducting drives signal on gate terminal (G1), electric current also can be from source electrode (S1) side direction drain electrode (D) side flow, be applied in the switch element (SW1 ') of described revers voltage, in gate terminal (G1) and drain electrode, have between (D) and only allow parasitic diode (Dgd1) between the gate-to-drain of electric current from this gate terminal (G1) effluent to drain electrode (D) side, with in order to drive to control the gate driver circuit (51) of described switch element (SW1 '), described gate driver circuit (51) comprises the grid voltage adjustment part (54) of adjusting voltage Vgd between gate-to-drain, so that voltage Vgd is less than the forward voltage Vf of parasitic diode (Dgd1) between described gate-to-drain between this gate-to-drain between gate terminal (G1) and drain electrode (D).
-effect of invention-
As mentioned above, according to the invention of first aspect, in two switch element SW1, SW2 of series connection, apply the switch element SW1 of revers voltage, even if be configured to that do not input on gate terminal G1 under the state that conducting state drives signal also can reverse conducting because be, so can cut down components and parts number, simplify circuit and form and seek to obtain the reduction of conduction loss, and be easy to easily carry out the control to a plurality of switch elements.
Also have, according to the invention of second aspect, the gate driver circuit 33 of described switch element SW1, because comprise the resistive element 44 in parallel with this switch element SW1 between source S 1 and gate terminal G1, so just can prevent from applying, surpass withstand voltage voltage between source S 1 and gate terminal G1, and can make described switch element SW1 become effective conducting state.
Also have, according to the invention of the third aspect, described switch element SW1 ', between gate terminal G1 and drain D, there is parasitic diode Dgd1 between gate-to-drain, because it is less than the forward voltage Vf of described parasitic diode Dgd1 to make this switch element SW1 ' become the threshold voltage vt of conducting state, so just can not make backward current flow through this parasitic diode Dgd1 but can make reverse circuit flow cross switch element SW1 ', the delay in the time of just can preventing from disconnecting and the increase of loss.
Also have, according to the invention of fourth aspect, described switch element SW1 ', between gate terminal G1 and drain D, there is parasitic diode Dgd1 between gate-to-drain, because the voltage Vgd adjusting between gate terminal G1 and drain D makes the voltage Vgd comparing between this gate terminal G1 and drain D with the forward voltage Vf of this parasitic diode Dgd1 little, so really can prevent that electric current from flowing through this parasitic diode Dgd1.
Also have, according to the invention of the 5th aspect, gate driver circuit 33,34, because be to be configured to gate terminal G1, the G2 of a plurality of switch element SW1, SW2 to input same driving signal, controls so just can easily carry out the driving of a plurality of switch element SW1, SW2.
Also have, according to the invention of the 6th aspect, because be to export off-state control signal to applying the switch element SW1 of revers voltage, so can interdict the electric current of the forward flow of this switch element SW1, can obtain more really can carrying out the bidirectional switch circuit 30 of two-way switching.
Also have, according to the invention of the 7th aspect, because described switch element SW1, SW2 are arranged on a device, so seek to such an extent that the chip area of reduction of device reduces the wastage.
Also have, according to the invention of eight aspect, because can guarantee that two distances between gate electrode are larger, so just can improve between two source terminals i.e. withstand voltage between drain electrode-source electrode.
Also have, according to the invention of the 9th aspect, because matrix hands over-hands over arbitrary bidirectional switch circuit of invention that transducer 60 comprises described first to fourth aspect as switch portion, even if so hand over-hand in transducer 60 at this matrix, also can obtain the effect identical with the invention of described first to fourth aspect.Particularly, as the invention of the tenth aspect, matrix is handed over-is handed in transducer 60, by switch element Sur1, Sur2 being arranged in a device, just can obtain the effect same with the invention of described the 7th aspect.Also have, according to the invention of described the tenth one side, because can guarantee that two distances between gate electrode are for larger, so just can obtain the effect same with the invention of eight aspect.
Have again, according to the invention of the 12 aspect because power conversion device 1,1 ' comprise described first to the bidirectional switch circuit in the invention of eight aspect either side as switch portion, so just can obtain with first to the same effect of the invention of eight aspect.
Embodiment
Below, based on accompanying drawing, describe execution mode involved in the present invention in detail.In addition, following explanation preferred embodiment, is only an example in essence, has no intention to limit the present invention and applicable thing thereof or its purposes.
(the first execution mode)
An example that has represented the circuit of the power conversion device 1 that the first execution mode of the present invention is related in Fig. 1.This power conversion device 1, comprise ac-dc converter circuit 11, times potential circuit 12, smoothing capacity 13, DC conversion circuit 14 and power factor improvement circuit 15, be configured to and will for the alternating voltage coming, change from AC power 2 voltage of assigned frequency, the load 3 of supply three-phase alternating current motor etc. into.
Described ac-dc converter circuit 11, is connected in described AC power 2, and being configured to ac voltage rectifier is direct current.This ac-dc converter circuit 11, is to be connected to by a plurality of (being four) diode D1~D4 the diode-bridge circuit that bridge-type forms in Fig. 4 example, through reactance coil (L), is connected in AC power 2.Thus, the alternating voltage of described AC power 2, changes direct voltage into by the bridge circuit of described diode D1~D2.
Described voltage-multiplying circuit 12, comprises two electric capacity 21,22 of series connection.This voltage-multiplying circuit 12, the one end that is described AC power 2 is connected between these electric capacity 21,22 and forms through described ac-dc converter circuit 11, so described electric capacity 21,22 is recharged, the voltage at the series circuit two ends of electric capacity 21,22 becomes the electric charge of the voltage twice of described AC power 2.
Described smoothing capacity 13, be for smoothly by described ac-dc converter circuit 11 and voltage-multiplying circuit 12 rectifications the capacitor of direct voltage.
Described DC conversion circuit 14 is all in parallel with ac-dc converter circuit 11 with described voltage-multiplying circuit 12 and smoothing capacity 13.This DC conversion circuit 14 is for example, by a plurality of switch element 14a when three-phase alternating current (be six), to connect into bridge-type to form.That is to say, not special diagram, but described DC conversion circuit 14, that three, the switch pin (switching leg) being mutually in series by two switch element 14a, 14a is formed in parallel, be configured to and utilize the switch motion of these switch elements 14a that direct voltage is transformed into alternating voltage, supply with load 3.In addition, in present embodiment, as shown in Figure 1, described each switch element 14a, is formed by transistor and diode parallel connected in reverse phase, but be not limited to this, so long as be configured to can switch formation, other formation also can.
Described power factor improvement circuit 15, comprises the bidirectional switch circuit 30 with bidirectional switch 31 that can two-way admittance, and the two ends of described bidirectional switch 31 are connected in this AC power 2 and make the described AC power 2 can short circuit.Described power factor improvement circuit 15, be configured to according to the polarity of voltage of AC power 2 and drive and control bidirectional switch 31, so that these AC power 2 short circuits, by the combination with described reactance coil L, the input current Is of this power factor improvement circuit 15 is carried out to rectification, improve the size of electrical source power factor and control voltage Vpn.
Specifically, described power factor improvement circuit 15, comprises described bidirectional switch circuit 30 and the zero cross detection portion 32 corresponding to the zero cross signal Sz of the polarity of voltage of described AC power 2 to these switching circuit 30 outputs.This zero cross detection portion 32, is configured to the waveform corresponding to the alternating voltage of described AC power 2, the zero cross signal Sz of every half period generating output signal (ON-OFF) upset output.
Described bidirectional switch circuit 30, comprise be configured to can two-way admittance bidirectional switch 31, this bidirectional switch 31 output drive signal Vg1, Vg2 are driven to drive circuit 33,34 and the power factor improvement control part 35 (control part) to this drive circuit 33,34 output control signal Sg1, Sg2 of this bidirectional switch 31.This power factor improvement control part 35, if be configured to input from the zero cross signal Sz of described zero cross detection portion 32 outputs, based on this zero cross signal Sz, the control signal Sg1, the Sg2 that in order to drive, control bidirectional switch 31 are exported to described drive circuit 33,34.
Described bidirectional switch 31, is that two switch element SW1, SW2 are in series in the interconnective mode that drains, and by being driven and controlled this switch element SW1, SW2 by described drive circuit 33,34, being configured to can two-way admittance.Described switch element SW1, SW2, such as being to answer transistor, hetero junction field effect transistor npn npn, High Electron Mobility Transistor etc. to form by junction field effect transistor and static induction transistor, metal-semiconductor field effect type, be configured to and apply than drain side also under the state of high voltage (hereinafter referred to as revers voltage) in source side, even if do not have on gate terminal in the situation of input drive signal, electric current also flows from source side to drain side.In addition, described switch element SW1, SW2, as shown in Fig. 2 (a), be provided with two source terminal S1, S2 and gate terminal G1, G2 and total drain side, namely can be formed by so-called double gated device, also can by separately independently device form.In addition, Fig. 2 (b), is so-called double gated device, to consist of the example of the circuit mark in the situation of switch element SW1, SW2.In switch element SW1, the SW2 of described double gated, preferably the distance of two gate electrodes is larger than mutually corresponding gate electrode and the distance between source electrode.That is to say, in the example of Fig. 2 (a), make the distance of 1 of source S 1-grid G be less than the distance of 2 of grid G 1-grid G, and the distance of 2 of source S 2-grid G to be less than the distance of 2 of grid G 1-grid G better.This is because in the device of described double gated, and withstand voltage between two source terminal S1, S2 is to be subject to two withstand voltage left and right between gate terminal G1, G2, by the interelectrode distance of regulation, guarantees that resistance to pressure just becomes possibility fully as mentioned above.
At this, set on state resistance Ron to described switch element SW1, SW2, make by the on state voltage producing to the mobile backward current of drain side from source side, the threshold voltage vt that becomes conducting state than switch element SW1, SW2 is high.Thus, just can make the voltage between gate-to-drain more promptly reach voltage more than described threshold voltage vt.Therefore, just can more promptly make described switch element SW1, SW2 become conducting driving condition, the loss in the time of can also reducing current lead-through.In addition, in the transistor such as junction field effect transistor and static induction transistor, threshold voltage is below 2.5V, like this can be so that described on state resistance be less, so even if the formation that on state voltage as described above reaches more than threshold voltage also can reduce the conduction loss of switch element.
Thus, at length as described later, in described switch element SW1, SW2, source side applies high-tension switch element SW1, even if do not drive control in conducting state, also can become the possible state of reverse conducting by the revers voltage that acts on this switch element SW1.Therefore,, in present embodiment, only drive and control the switch element SW1 that drain side is applied to the voltage higher than source side.
-drive circuit-
Based on Fig. 3 explanation, in order to driving, control the formation of the drive circuit 33,34 with the above switch element SW1, SW2 forming like that below.In addition, as shown in Figure 3, drive circuit 33,34, because have identical formation, so a drive circuit 33 is only described below, formation identical with this drive circuit 33 in another drive circuit 34 marks identical symbol.
Described drive circuit 33, comprises that in order to 1 of the grid G-source S at switch element SW1, applying the driving power 41 of voltage Vg, two grids carrying out switch motion in response to the control signal Sg1 from power factor improvement control part 35 output drives with switch element 42,43 with at 1 resistance 44 (resistive element) in parallel with this switch element SW1 of grid G-source S of described switch element SW1.
Described grid drives with switch element 42,43 and mutually connects, and the gate terminal G1 of described switch element SW1 is connected between these switch elements 42,43.Grid drives with switch element 43, be configured between described driving power 41 and the gate terminal G1 of switch element SW1, when this switch element 43 is formed on conducting state described in the voltage Vg of driving power 41 be applied to the voltage supply circuit on the gate terminal G1 of switch element SW1.On the other hand, grid drives with switch element 42, be set to this switch element 42 when conducting state by the source side S1 of switch element SW1 and gate terminal G1.In addition, in described Fig. 3, symbol 45, is arranged on grid driving and uses between switch element 42,43 and the gate terminal G1 of switch element SW1, adjusts the switching speed resistance of switch element SW1.
Also have, the described grid of series connection drives with switch element 42,43, correspond respectively to from the control signal Sg1 of described power factor improvement control part 35 outputs, by drive control part 46,47, drive and control, while making a side be conducting state, the opposing party is off-state, and a side is while being off-state and the opposing party is conducting state.
Thus, utilizing the driving of control signal Sg1 grid to become conducting state with switch element 43, and grid drives to be become in the situation of off-state with switch element 42, is applied in the voltage Vg of driving power 41 on the gate terminal G1 of switch element SW1, and this switch element SW1 starts working.In this case, the input of the gate terminal G1 from drive circuit 33 to switch element SW1 conducting state drives signal Vg1.
On the contrary, by control signal Sg1, grid drives becomes conducting state with switch element 42, and grid driving becomes in the situation of off-state with switch element 43, on the gate terminal G1 of switch element SW1, do not apply the voltage Vg of driving power 41, this switch element SW1 becomes off-state.In this case, the input of the gate terminal G1 from drive circuit 33 to switch element SW1 is not that conducting drives signal but disconnection control signal.
Between the grid G 1-of described switch element SW1 source S 1, the described resistance 44 in parallel with described switch element SW1 has than the abundant little resistance value of this switch element, make when being applied in revers voltage on described switch element SW1, between the grid G 1-drain D of this switch element SW1, almost former state applies revers voltage.That is, by making described resistance 44 have fully little resistance value, voltage acts between the source S 1-grid G 1 of the switch element SW1 in parallel with this resistance 44 hardly, and described revers voltage acts between the grid G 1-drain D of this switch element SW1.
-action of bidirectional switch circuit-
Below, based on Fig. 1 to Fig. 5, the action with above such bidirectional switch circuit 30 forming is described.
First, illustrate to drive the action of drive circuit 33,34 of switch element SW1, the SW2 of the bidirectional switch 31 in bidirectional switch circuit 30.
As shown in Figure 3, Figure 4, at t=t0, if on bidirectional switch 31, switch element SW1 being applied with respect to switch element SW1 is the supply voltage Vdc of reverse (the high state of voltage ratio drain side D of source side S1),, by resistance 44 being set on the drive circuit 33 at this switch element SW1, the voltage being applied on this switch element SW1 has all been added between grid G 1-drain D substantially.Like this, the voltage Vsg that source S 1-grid G is 1 is zero substantially, and the voltage Vgd between the voltage Vsd between source S 1-drain D and grid G 1-drain D remains the threshold voltage vt that switch element SW1 becomes conducting state.Like this, a switch element SW1 of bidirectional switch 31 is upper, because be only applied in the voltage of threshold voltage vt, so another switch element SW2 of bidirectional switch 31 is upper, applies remaining voltage Vdc-Vt.In addition, this switch element SW2 is upper, because input conducting state, does not drive signal, and the voltage Vgs that just becomes 2 of grid G 1-source S is zero, the state of the whole voltages that apply Vdc-Vt that drain D-grid G is 2.
Next, at t=t1, if the Continuity signal of input control signal Sg2 on the drive circuit 34 of described switch element SW2, the grid of drive circuit 34 drives becomes conducting state with switch element 43, and voltage Vg is just applied to the gate terminal G2 of described switch element SW2 from driving power 41.Like this, the switch element SW2 of institute becomes conducting state, and electric current I s is interior mobile at bidirectional switch 31.That is, described switch element SW2 become conducting state during become ton during conducting state.
At this, the voltage Vds that drain D-source S of described switch element SW2 is 2, if this switch element SW2 becomes conducting state, once then vanishing increases slowly corresponding to the electric current that flows through this switch element SW2.On the other hand, described switch element SW1 also, the voltage Vgd between the voltage Vsd between source S 1-drain D and grid G 1-drain D, the voltage producing due to the electric current in this switch element SW2 increases slowly.
And, at t=t2, if inputting the control signal Sg2 of the drive circuit 34 of described switch element SW2 is off-state, the grid of this drive circuit 34 drives becomes off-state with switch element 43, on the gate terminal G1 of described switch element SW2, do not apply the voltage Vg of driving power 41, the voltage Vgs that grid G 2-source S is 2 is zero.Like this, each voltage of described switch element SW1, SW2, becomes the state identical with t=t0.
The figure that the arrangements such as the waveform of the action of drive circuit 33,34 as described above and supply voltage and zero cross signal Sz are recorded is illustrated in Fig. 5.In addition, in this Fig. 5, when zero cross signal Sz is conducting state, on the switch element SW1 of bidirectional switch 31, apply revers voltage, and zero cross signal Sz is while becoming off-state, on switch element SW2, applies revers voltage.
As described in as shown in Fig. 5, when applying revers voltage on switch element SW1, SW2, even if there is no input drive signal on this switch element SW1, SW2, as long as voltage Vgd, the Vdg between grid G 1, G2-drain D is on threshold voltage vt, just become conducting state.And, driving to control to make the opposing party's switch element become conducting state, electric current I s will flow in bidirectional switch 31.
-effect of the first execution mode-
As mentioned above, according to this execution mode, switch element SW1, SW2 as bidirectional switch 31, in source S 1 side, apply under the state (being applied in the state of revers voltage) of the voltage higher than drain D side, even if do not input on gate terminal G1, G2 in the situation of conducting state driving signal, by using electric current to flow to the switch element of drain D side from source side S1, as long as only drive and be controlled at the switch element that drain D side applies the voltage higher than source S 2 sides, just can carry out the energising of bidirectional switch 31 and control.Therefore, the driving of switch element SW1, the SW2 of described bidirectional switch 31 is controlled and is just become easy.
And, by the above such formation, because no longer need existing necessary diode, just can reduce the quantity of this part components and parts, seek the simplification of circuit formation and the reduction of conduction loss.
The variation 1-of the-the first execution mode
This variation 1, as shown in Figure 6, just at the power factor improvement control part 35 ' from power conversion device 1 ', only export a control signal Sg1, in switch element SW1, the SW2 of bidirectional switch 31, input identical driving signal (Vg1=Vg2) this point different from described the first execution mode, so the part identical with this first execution mode marks same symbol, below different parts is only described.
Specifically, as described in as shown in Fig. 6, from the power factor improvement control part 35 ' of the 32 input zero cross signal Sz of zero cross detection portion, be configured to control signal Sg1 exported to drive circuit 33,34.Thus, because to the identical control signal Sg1 of described drive circuit 33,34 input, so as shown in Figure 7, export respectively identical driving signal Vg1, Vg2 from this drive circuit 33,34 to switch element SW1, SW2.
Like this, by two switch element SW1, SW2 to bidirectional switch 31, input identical signal, compare control with the situation that drives respectively this switch element of control SW1, SW2 and become easy.
At this, usually, as mentioned above, if input identical signal to two switch element SW1, SW2 of bidirectional switch 31, due to deviation of the performance of switch element etc., switch element become conducting state time be carved with situation about departing from.Therefore, by the switch element SW1, the SW2 that use described the first execution mode to form like that, be applied in the switch element of revers voltage, independently become conducting state with the driving signal to gate terminal G1, G2, therefore just can prevent that this switch element from sustaining damage.
The variation 2-of the-the first execution mode
This variation 2, as shown in Figure 8, just in thering are two switch element SW1 ', SW2 ' of bidirectional switch 31 ', between gate terminal G1 ', G2 '-drain D, be formed with parasitic diode Dgd1, Dgd2, and described switch element SW1 ', SW2 ' have does not make electric current different from described the first execution mode in the formation this point of this parasitic diode Dgd1, dgd2 side flow, so the part identical with this first execution mode marks same symbol, below different parts is only described.
Specifically, as described in as shown in Fig. 8, switch element SW1 ', SW2 ' are provided with respectively between grid G 1, G2-drain D can only be from parasitic diode Dgd1, the Dgd2 of gate terminal G1, the conducting of G2 side direction drain D side.And described switch element SW1 ', SW2 ', be configured to that to become the threshold voltage vt of conducting state less than the forward voltage Vf of described parasitic diode Dgd1, Dgd2.
Thus, electric current is at described parasitic diode Dgd1, and before Dgd2 side flow, described switch element SW1 ', SW2 ' become the upper circulating current of this switch element of conducting state SW1 ', SW2 '.Usually, if the upper circulating current of parasitic diode Dgd1, Dgd2, in this parasitic diode Dgd1, Dgd2, accumulated minority carrier produce delay while disconnecting or with flow through in this parasitic diode Dgd1, Dgd2 when produce larger loss, but by making described such formation and in switch element SW1 ', SW2 ' effluent galvanization, the delay in the time of just can preventing from disconnecting and the increase of loss.
The variation 3-of the-the first execution mode
This variation 3, as shown in Figure 9, the same with described variation 2, just between the gate terminal G1 of switch element SW1 ', the SW2 ' of bidirectional switch 31 ', G2-drain D, form parasitic diode Dgd1, Dgd2 this point, and the driving power 53 of drive circuit 51,52 to be configured to this point of voltage variable different from described the first execution mode, so the part identical with this first execution mode marks same symbol, below different parts is only described.
Specifically, as described in as shown in Fig. 9, to switch element SW1 ', SW2 ' respectively between grid G 1, G2-drain D, be provided with can be only from parasitic diode Dgd1, the Dgd2 of this gate terminal G1, G2 side direction drain side D conducting.
In the drive circuit 51,52 of described switch element SW1 ', SW2 ', be respectively arranged with the driving power 53 that is configured to voltage variable.Also have, described drive circuit 51,52, comprise that the electric current I s based on mobile in bidirectional switch 31 ' obtains the voltage Vgd between grid G 1, G2-drain D, the voltage of adjusting described driving power 53 makes the always grid voltage adjustment part 54 less than the forward voltage Vf of described parasitic diode Dgd1, Dgd2 of this voltage Vgd.
In detail, because the voltage Vsd between source S 1, S2-drain D, (=Is * Ron (on state resistance of switch element SW1 ', SW2 ')) that electric current I s mobile in corresponding bidirectional switch 31 ' changes, so described grid voltage adjustment part 54, be configured to corresponding to described voltage Vsd and change the voltage Vgs (voltage of driving power 53) between grid G 1, G2-source S 1, S2, make the voltage Vgd between grid G 1, G2-drain D always little than the forward voltage Vf of described parasitic diode Dgd1, Dgd2.
Thus, because can make the grid G 1 of switch element SW1 ', SW2 ', the voltage Vgd between G2-drain D always little than the forward voltage Vf of described parasitic diode Dgd1, Dgd2, so can really prevent circulating current in this parasitic diode Dgd1, Dgd2.Therefore the generation of delaying in the time of, also just really can preventing from disconnecting and the increase of loss.
The variation 4-of the-the first execution mode
This variation 4, as shown in figure 10, because just between the source S 1 of the switch element 56,57 of bidirectional switch 55, S2-drain D, be formed with parasitic diode Dgd1, Dgd2 this point is different from described the first execution mode, so the part identical with this first execution mode marks same symbol, below different parts is only described.
Specifically, to the switch element 56,57 of bidirectional switch 55 only between source S 1, S2-drain D, be provided with can conducting from source S 1, S2 side direction drain D side parasitic diode Dgd1, Dgd2.That is, described switch element 56,57, has parasitic diode Dgd1, Dgd2 between source S 1, S2-drain D, by forming such as MOSFET etc.
Thus, even if in the situation that apply source S 1, revers voltage that S2 side is higher than drain D side on described switch element 56,57, till this switch element 56,57 becomes conducting state, because electric current can flow in described parasitic diode Dgd1, Dgd2, so the loss in the time of just can reducing described switch element 56,57 for off-state.
(the second execution mode)
-whole formation-
The summary that has represented the power conversion device 60 that the second execution mode of the present invention is related in Figure 11 forms.This power conversion device 60, is that the alternating current directly AC power from certain frequency 61 being obtained carries out the alternating current that power transfer becomes another frequency, and transducer (matrix converter) is handed over-handed over to so-called matrix.
Transducer 60 is handed over-handed over to described matrix, comprises a plurality of (in illustrated example being six) bidirectional switch Sur, Sus, Sut, Svr, Svs, Svt as switch portion.In addition, in the example of described Figure 11, transducer 60 is handed over-handed over to described matrix, be configured to and will be transformed into the loads 62 such as monophase current supply motor from the alternating current of three-phase alternating-current supply 61 outputs, but be not limited to this, such as being the formation etc. of supplying with load using the alternating current of three-phase alternating-current supply 61 as three-phase alternating current, can be also other any formations.
Described a plurality of bidirectional switch Sur, Sus, Sut, Svr, Svs, Svt, be set to be connected in selectively with respect to the import and export side of described load 62 terminal of each phase of described AC power 61.Specifically, form on two terminals of import and export side of described load 62, connecting respectively three bidirectional switchs of each phase terminal that connects separately described AC power 61.By these bidirectional switchs Sur, Sus, Sut, Svr, Svs, Svt, in transducer 60 is handed over-handed over to described matrix, form in the import and export side of described load 62, respectively with the R phase being respectively connected, S phase and the T phase of described AC power 61.
Have the matrix forming as described above and hand over-hand in transducer 60, as shown in Figure 12 (a), if for example make bidirectional switch Sur, the Svt of R phase and T phase become conducting state, electric current I u will flow through matrix and hand over-hand between the R phase and T phase of transducer 60.And, as shown in Figure 12 (b), if make the bidirectional switch Sur of R phase, be off-state, and S phase bidirectional switch Sus become conducting state, electric current hands over-hands over the S phase of transducer 60 and T to flow between mutually at matrix.That is,, by carrying out the such switch motion of described Figure 12, carry out the turn of tidal stream action of matrix friendship-friendship transducer 60.
-formation of bidirectional switch and action-
The concrete formation of described bidirectional switch Sur, Sus, Sut, Svr, Svs, Svt is below described.In addition, each bidirectional switch Sur, Sus, Sut, Svr, Svs, Svt, because have same formation, so bidirectional switch Sur, the Sus of R phase and S phase are only described below.
Before explanation formation of the present invention, first formation and the action thereof of existing bidirectional switch Sur ', Sus ' are described based on Figure 13 to Figure 15.
As described in as shown in Figure 13, each bidirectional switch Sur ', Sus ', it is reverse that reverse parallel connection makes the conducting direction of this diode Dur1 ', Dur2 ', Dus1 ', Dus2 ' in the circuit of switch element Sur1 ', Sur2 ', Sus1 ', Sus2 ' and diode Dur1 ', Dur2 ', Dus1 ', Dus2 ' series connection.These diodes Dur1 ', Dur2 ', Dus1 ', Dus2 ', with respect to switch element Sur1 ', Sur2 ', Sus1 ', Sus2 ' be connected in series make this switch element Sur1 ', Sur2 ', Sus1 ', Sus2 ' can only forward (circulating direction of electric current when the voltage of the voltage ratio source side of drain side is high) conducting.That is, described bidirectional switch Sur ', Sus ', have the formation of two reverse parallel connections of circuit that can only one-way conduction, thus can two-way admittance.
In addition, the formation of described bidirectional switch Sur ', Sus ', beyond the formation of described Figure 13, in addition will with respect to switch element Sur1 ', the reverse parallel connection of Sus2 ' circuit of diode Dur1 ', Dur2 ', known to making switch element Sur1 ', Sus2 ' and diode Dur1 ', Dur2 ' the such formation of Figure 14 of series connection of reverse prevention being also between separately.In Figure 13 and Figure 14, solid arrow represents that electric current I u flows through the situation of R phase, and dotted arrow represents that electric current I u flows through the situation of S phase.
Next, there is existing bidirectional switch Sur ' as described above, the action of Sus ' with explanation together with the turn of tidal stream action of matrix AC/DC changeover switch.At this, Figure 15, expression from R in opposite directions S carry out mutually the bidirectional switch Sur ' of turn of tidal stream action, the action of Sus ', Figure 15 (a) represents that electric current I u be on the occasion of situation, and Figure 15 (b) expression electric current I u is the bidirectional switch Sur ' of negative value situation, the action of Sus '.Also have, in Figure 15, with real oblique line, be illustrated in R and apply than the conducting situation under the mutually high voltage status of S on mutually, and with empty oblique line, be illustrated in the situation of the switch element that in the situation that S applies the voltage mutually higher than R on mutually, switching is switched on.
In addition, not special diagram, transducer is handed over-handed over to described matrix, the polarity of voltage detection part of polarity or the Current polarity detection parts of detection current polarity that comprise the voltage that detects AC power, based on this testing result, determine the moment (from t0 to t7) of the switch motion of bidirectional switch Sur ', Sus '.
First, electric current I u be on the occasion of situation under, as shown in Figure 15 (a), during t=t0, switch element Sur1 ' becomes conducting state, electric current I u flows through R phase.At this moment, another switch element Sur2 ' in the bidirectional switch Sur ' of R phase also becomes conducting state.This is because when load 62 sides are short-circuited fault, make electric current reverse flow, former to prevent that matrix from handing over-handing over transducer to break down.
Make electric current I u when phase, first at t=t1, make described switch element Sur2 ' become off-state from R phase turn of tidal stream to S.And, at ensuing t=t2, drive the switch element Sus1 ' that controls the bidirectional switch Sus ' that makes S phase to become conducting state.At this moment, if apply the state (Vrs>0) of higher voltage mutually than S on mutually at R, R goes up electric current Iu continue to flow (Sur1 ' solid line part) mutually, and if apply the state (Vrs<0) of higher voltage mutually than R on mutually at S, electric current I u flows changes mutually and becomes mutually S phase (from the dotted portion of the solid line part break-in Sur1 ' of Sur1 ') from R.At t=t3, if make described switch element Sur1 ' become off-state, even if Vrs>0, the mobile phase of electric current I u also becomes S phase (partly becoming the solid line part of Sus1 ' from the solid line of Sur1 ') mutually from R.
By doing like this, can by the mutually mobile electric current I u turn of tidal stream of R to S phase.Thereafter, at t=t4, drive another switch element Sur2 ' that controls the bidirectional switch Sus ' make S phase also to become conducting state, reverse when fault etc. also have a current flowing.
On the contrary, make electric current I u from S phase turn of tidal stream to R, when phase, first at t=t5, described switch element Sus2 ' be become after conducting state once again, at ensuing t=t6, drive the switch element Sur1 ' of the bidirectional switch Sur ' that controls R phase to become conducting state.At this moment, if apply the state (Vrs>0) of higher voltage mutually than S on mutually at R, what electric current I u was mobile becomes R phase (partly becoming the solid line part of Sur1 ' from the solid line of Sus1 ') mutually from S, and if apply the state (Vrs<0) of higher voltage mutually than R on mutually at S, the phase that electric current I u is mobile or at S phase (Sus1 ' dotted portion).If make switch element Sus1 ' become off-state at t=t7, even if Vrs<0, the mobile phase of electric current I u also can become R phase (becoming the solid line part of Sur1 ' from the dotted portion of Sus1 ') mutually from S.Completed thus the turn of tidal stream action of the electric current I u of R phase in opposite directions from S.
In turn of tidal stream action as above, because by making the action of switch element Sur1 ', Sus1 ' and the action of switch element Sur2 ', Sus2 ' reciprocal, can realize the turn of tidal stream action of described Figure 15 (b), so omit the action specification of the situation of this Figure 15 (b).
Yet, there is the above bidirectional switch Sur ' forming like that, the situation of Sus ', because outside switch element Sur1 ', Sur2 ', Sus1 ', Sus2 ', also need to be in order to stop reverse prevention diode Dur1 ', Dur2 ', Dus1 ', the Dus2 ' of electric current reverse flow, so component number is many, circuit forms the complexity that also becomes, and it is large that conduction loss also becomes thereupon, becomes problem.To this, expected adopting the formation of omitting diode Dur1 ', Dur2 ', Dus1 ', Dus2 ' use reverse blocking IGBT, but in order to prevent that the destruction of switch element is necessary constantly to drive and control this switch element well, needed the control of high accuracy and complexity.
To this, in present embodiment, in order to reduce component number, simplify circuit and reduce conduction loss, and by the simple driving of switch element, controlled the bidirectional switch of can realization matrix handing over-hand over transducer, as the switch element of bidirectional switch, used to be configured in source side to apply under the state of the voltage higher than drain side, even if the in the situation that of there is no input drive signal on gate terminal, electric current also can be from source side to the mobile device of drain side.
Specifically, as shown in figure 16, bidirectional switch Sur, the Sus of transducer 60 handed over-handed over to matrix, in the connected mode of drain side of two switch element Sur1, Sur2, Sus1, Sus2, connects.And, described each switch element Sur1, Sur2, Sus1, Sus2, be configured in source side and apply under the state of the voltage higher than drain side, even if input conducting state on gate terminal, do not drive signal, electric current also can flow from source side to drain side.Described switch element SW1, SW2, such as being to answer transistor, the opposite sex to engage field-effect transistor, High Electron Mobility Transistor etc. by junction field effect transistor and static induction transistor, metal semiconductor electric field effect type to form.In described Figure 16, solid arrow represents that electric current I u flows through the situation of R phase, and dotted arrow represents that electric current I u flows through the situation of S phase.
At this, form two switch element Sur1, Sur2, Sus1, the Sus2 of described each bidirectional switch Sur, Sus, the same with switch element SW1, the SW2 of described the first execution mode, be provided with two source terminal S1, S2 and gate terminal G1, G2 and total drain D, namely can be formed by so-called double gated device, also can by separately independently device form.
Described switch element Sur1, Sur2, Sus1, Sus2, set on state resistance Ron and make by the on state voltage producing to the mobile backward current of drain side from source side, and the threshold voltage vt that becomes conducting state than switch element SW1, SW2 is high.Thus, just can make the voltage between gate-to-drain more promptly reach voltage more than described threshold voltage vt.Therefore, just can more promptly make described switch element Sur1, Sur2, Sus1, Sus2 become conducting driving condition, the loss in the time of can also reducing backward current conducting.In addition, in the transistor of junction field effect transistor and static induction transistor etc., threshold voltage is below 2.5V, like this can be so that described on state resistance be less, so even if the formation that on state voltage as described above reaches more than threshold voltage also can reduce the conduction loss of switch element.
Thus, at length as described later, in described switch element Sur1, Sur2, Sus1, Sus2, source side applies high-tension switch element, even if in the not driven control of conducting state, also can become the possible state of reverse conducting by the revers voltage that acts on this switch element.
In addition, because the drive circuit of described switch element Sur1, Sur2, Sus1, Sus2 is the same with described the first execution mode, so omit the explanation that forms and move.That is to say, in Fig. 3 of described the first execution mode, switch element SW1, SW2 are corresponding with switch element Sur2, Sus2 and switch element Sur1, Sus1 in present embodiment respectively.
Described switch element Sur1, Sur2, Sus1, Sus2 are made to the bidirectional switch Sur of the above situation about forming like that, the action of Sus, explanation together with the turn of tidal stream action of handing over-handing over transducer with matrix.At this, Figure 17, expression from R in opposite directions S carry out mutually the bidirectional switch Sur turn of tidal stream action situation, the action of Sus, Figure 17 (a) represent electric current I u be on the occasion of time bidirectional switch Sur, the action of Sus, bidirectional switch Sur when Figure 17 (b) expression electric current I u is negative value, the action of Sus.In addition, in described Figure 17, with real oblique line, be illustrated in R and apply than the conducting situation under the mutually high voltage status of S on mutually, and be illustrated in empty oblique line the situation of switching the switch element of energising in the situation that S applies the voltage mutually higher than R on mutually.
In addition, not special diagram, transducer is handed over-handed over to described matrix, the polarity of voltage detection part of polarity or the Current polarity detection parts of detection current polarity that comprise the voltage that detects AC power, based on this testing result, determine the moment (from t0 to t7) of the switch motion of bidirectional switch Sur ', Sus '.
First, electric current I u be on the occasion of situation under, as shown in Figure 17 (a), during t=t0, switch element Sur1 becomes conducting state, electric current I u flows through R phase.At this moment, another switch element Sur2 in the bidirectional switch Sur of R phase also becomes conducting state.
Make electric current I u when phase, first at t=t1, make described switch element Sur2 become off-state from R phase turn of tidal stream to S.Therefore, because be applied in revers voltage on this switch element Sur2, even if so on the gate terminal of this switch element Sur2, do not input the state that conducting state drives signal, at R, execute that alive state continues on mutually during electric current I u flow through this switch element Sur2.
And, at ensuing moment t=t2, drive the switch element Sur1 that controls the bidirectional switch Sus that makes S phase to become conducting state.At this moment, if apply the state (Vrs>0) of higher voltage mutually than S on mutually at R, R goes up electric current Iu continuation mobile (the solid line part of Sur1) mutually, and if apply the state (Vrs<0) of higher voltage mutually than R on mutually at S, electric current I u flows changes mutually and becomes mutually S phase (from the dotted portion of the solid line part break-in Sur1 of Sur1) from R.At t=t3, if make described switch element Sur1 become off-state, even if Vrs>0, the mobile phase of electric current I u also becomes S phase (partly becoming the solid line part of Sus1 from the solid line of Sur1) mutually from R.At this, as mentioned above, only make the switch element Sus1 of the bidirectional switch Sus of S phase become conducting state, S applies the such voltage of current flowing Iu on mutually, even and if on the gate terminal of another switch element Sus2 of the bidirectional switch Sus of S phase, do not input the state that conducting state drives signal, this switch element Sus2 becomes state that can conducting, S mutually in current flowing Iu.
By doing like this, can will to S, go up mutually at the mutually mobile electric current I u turn of tidal stream of R.Thereafter, at t=t4, drive another switch element Sur2 that controls the bidirectional switch Sus that makes S phase also to become conducting state, the conduction loss of seeking this switch element Sus2 reduces.
On the contrary, make electric current I u from S phase turn of tidal stream to R, when phase, first at t=t5, make described switch element Sus2 become off-state once again.At this moment, because be applied in revers voltage on this switch element Sus2, even if so on the gate terminal of this switch element Sus2, do not input the state that conducting state drives signal, at S, execute that alive state continues on mutually during electric current I u can in this switch element Sus2, flow.
At ensuing t=t6, drive control so that the switch element Sur1 of the bidirectional switch Sur of R phase become conducting state thereafter.At this moment, if apply the state (Vrs>0) of higher voltage mutually than S on mutually at R, what electric current I u was mobile becomes R phase (partly becoming the solid line part of Sur1 from the solid line of Sus1) mutually from S, and if apply the state (Vrs<0) of higher voltage mutually than R on mutually at S, the phase that electric current I u is mobile or at S phase (dotted portion of Sus1).If make switch element Sus1 become off-state at t=t7, even if Vrs<0, what electric current I u was mobile becomes R phase (becoming the solid line part of Sur1 from the dotted portion of Sus1) mutually from S.At this, as mentioned above, if make the switch element Sur1 of the bidirectional switch Sur of R phase become conducting state, R applies the such voltage of current flowing Iu on mutually, and another switch element Sus2 of the bidirectional switch Sur of R phase is upper, because be applied in revers voltage, even if do not input the state that conducting state drives signal on the gate terminal of this switch element Sus2, this switch element Sus2 becomes state that can conducting, R mutually in current flowing Iu.Completed thus the turn of tidal stream action of the electric current I u of R phase in opposite directions from S.
In turn of tidal stream action as above, by making the action of switch element Sur1, Sus1 and the action of switch element Sur2, Sus2, carry out on the contrary, because can realize the turn of tidal stream action of described Figure 17 (b), so omit the action specification of the situation of this Figure 17 (b).
In addition, also, the same with described the first execution mode in this execution mode, can also be configured to the variation 1 of this first execution mode to variation 4.
-effect of the second execution mode-
As mentioned above, according to this execution mode, as formation matrix, hand over-hand over switch element Sur1, Sur2, Sus1, the Sus2 of bidirectional switch Sur, the Sus of transducer 60, used in source side and applied under the state of the revers voltage higher than drain side, even if do not input on gate terminal in the situation of conducting state driving signal, electric current also can be from source side to the mobile device of drain side, so just can omit check diode, cut down component number, responsively seek thus the reduction of miniaturization and cost, and seek the reduction of conduction loss.
And, as mentioned above, apply switch element Sur1, Sur2, Sus1, the Sus2 of revers voltage, even if do not drive to control, also do not become the possible state of conducting, just do not need constantly to control well all switch element Sur1, Sur2, Sus1, Sus2, control and just become easy.
(other execution mode)
Each described execution mode can also be following formation.
In described the first execution mode, in source side, be applied in and on the gate terminal of switch element SW1 of the voltage higher than drain side, do not input conducting state and drive signal, but be not limited to this, or when detect inferring when flowing through backward current on this switch element SW1, can on the gate terminal of this switch element SW1, input conducting state and driving signal.By doing like this, can drive this switch element SW1 to become conducting state, so compared with situation about not driving with regard to conducting, seek to obtain the reduction of conduction loss.Also have, in described the second execution mode, also, if detect or infer when flowing through backward current on switch element Sur2, Sus2, can promptly conducting be driven signal to input this switch element Sur2, Sus2.
-industrial applicability-
The present invention is particularly useful for the power conversion device that comprises the bidirectional switch that a plurality of switch elements are connected.
-symbol description-
1 power conversion device
15 power factor improvement circuit
30 bidirectional switch circuit
31,31 ', 55, Sur, Sus bidirectional switch (switch portion)
32 zero cross detection portions (zero cross test section)
33 drive circuits (gate driver circuit)
34 drive circuits
33,35 ' power-factor improvement control part (control part)
41 driving powers
42,43 grid driving switch elements
44 resistance (resistive element)
45 resistance
46,47 drive control parts
51,52 drive circuits
53 driving powers
54 grid voltage adjustment parts
56,57 switch elements
60 power conversion devices (transducer is handed over-handed over to matrix)
Dgd1, Dgd2 parasitic diode
L reactance coil
SW1, SW2, SW1 ', SW2 ' switch element
S1, S2 source electrode
D drain electrode
G1, G2 gate terminal